One way that you can begin an analysis paper on these three stories is with an observation of how the surroundings in which person is immersed affects her or him.
This observation aligns with what the British writer W. Somerset Maugham once wrote,
It is very difficult to know people. For men and women are not only themselves, they are also the region in which they are born...the games they have played as children, the old wives' tales they overheard, the food they eat, the schools they have attended, the sports they follow, the poets they read, and the God they believe in.
These observations of Maugham hold so true in the case of Eveline in which her paralysis, as Joyce terms her inability to act, prevents her from breaking the hold of the religious promise she has made and her pledge to her dying mother to keep the family together. Moreover, her Irish culture holds her back from leaving the country with Frank as she reflects,
It was hard work--a hard life--but now that she was about to leave it she did not find it a wholly undesirable life.
Eveline's paralysis caused by her environment of Irish Catholicism prevents her leaving home.
In "Soldier's Home," by contrast, it is Harold Krebs who has changed because he has been pulled from his environment and, while he yet retains his love for his family, he cannot return to all that he once was because of his horrific experiences in the war. That is, as Thomas Wolfe wrote, he "cannot go home again" to the ingenuous youth that he was when he was drafted. For,he finds that the only way he can exist in his former surroundings is to lie about the war and to act like a child with his mother. "He wanted his life to go smoothly." Krebs escapes his environment, but must disconnect from his old identity.
In John Updike's story, somewhat as in Hemingway's narrative, the protagonist rejects his environment. However, in his rebellion against the "establishment" as represented by store manager Lengel and the varicose vein women, Sammy's ideas are but romantic illusions. So, when he quits his job as a chivalric gesture meant to impress Queenie, he finds himself alone because she and her friends have promptly left the store. Sammy stands outside the store and realizes he is yet dwelling in a complex world; furthermore, he learns that compromise with his environment is needed, not his romanticized rejection which has left him isolated when he cannot afford isolation as can Krebs.